Quantum Computing

4 min readMar 1, 2020

What is quantum computing: In a general ordinary computer uses bits like 0 and 1 for processing information but Quantum Computer uses quantum bits or qubits to process information, it can be 0 or 1 both 0,1 simultaneously. Quantum computer depends on qubits, as mush as qubits we use so a computer ‘s power grows exponentially.

The regular computer operates based on strict rules of logic, but tiny quantum object like an electron can break this rule.

So its power can be estimated that quantum computers could easily crack the codes that keep internet banking secure.

Qubit: Now building block or pillar of Quantum computing is the qubit. A qubit can represent a 1 or a 0 but most magical thing that it can achieve a mixed state called superposition. Where they can be both at the same time.

Superposition: Think of qubit as an electron in a magnetic field. The electron ‘s spin may be in alignment with a magnetic field is called the spin-up state and opposite to the field is known as the spin-down state. Charging electron’s spin from one state to another state by using pulse energy.

So what could Quantum computer be used for: According to its performance, it is very useful for government agencies, research development companies, universities in solving problems that current computers struggle with.

Currently, many online security systems run on the principle that its next to impossible to take a very large number and figure out that what’s next prime factors are. All a regular computer can do is try every possibility one after another so it can take billions of years, but if we use Shor’s algorithm, a Quantum computer performs within an hour.

It can be also in fantastic at recognizing patterns in data useful for machine learning examples to identify a different image, helpful for building a model to predict future such as weather forecasting.

How does superposition help?

difference between a regular computer and quantum computer boils down to how they approach to solve a problem.

Let us understand, A regular computer tries to solve a problem the same way you try to escape a maze -by trying every possible corridor, come back to a dead-end until you eventually find a way out. But superposition allows the Quantum computer to try all the paths at once and find the shortcut.

Regular computer based on two bits in four combinations at a time like 00,01,10,11. But the quantum computer, two qubits can also represent exact four states like a regular computer but the difference is that because of superposition it uses all four states at the same time such as four computers are working simultaneously.

if you add more bit in regular computer its performance not change but in Quantum computer, we add more bit so its power grows exponentially.

let us understand exponential growth. Its old fable about an ancient Indian called Sessa. Who invented chess. The king was delighted to the game and asked Sessa to name his reward. Sessa humbly requested a single chessboard with one grain of wheat on the first square, two on second, four on the third and so on. King agreed not realizing that he would promise away more wheat than existed on earth. It is the power of exponential growth.

Create the superposition?

If I say that have you tried to balance a coin exactly on its edge, that’s what programming qubits are like. It involves doing something to a qubit so that it ends up balanced between states.

Read information from the qubits?

Reading the qubits causes the superposition to collapse, like banging your first on the table with all those balanced coins. Here ‘s where a quantum algorithm shor comes into the picture. It loads the qubits to make them more likely to fall on the correct side and give us the right answer

Have any quantum computers been built yet?

In October 2019, a sycamore processor created in conjunction with google AI quantum was reported to have achieved quantum supremacy with calculation more than 3,000,000 times as fast as those of the summit.

What’s stopping us? Why is it so difficult to build a quantum computer?

Although we know the theory of quantum computers, there are challenges at every level from assembling qubit, also reading the information from a qubit, writing information on them. The truth we don’t know how long it will take time but we are trying our best at a global level. Every country researcher, engineers, scientist are working on it